1. Technical Field
The present invention relates to a method of forming a wiring pattern using a droplet discharge method, and more specifically, to a method of forming a wiring pattern which is suitable for formation of a gate electrode for a TFT.
2. Related Art
A technique for forming metal wiring lines by the ink jet method has been known in the related art (e.g., Japanese Unexamined Patent Application Publication No. 2004-6578).
The width of the gate electrode for a TFT is about 10 μm. In particular, the size (diameter) of a droplet which can be stably discharged by a head of an existing droplet discharge device is greater than the width of the gate electrode. For this reason, if droplets of a conductive material for forming the gate electrode are dropped in a region in which the gate electrode will be formed, there is a case where the droplet is attached onto other regions outside that region. The droplet that is attached outside that region generates residual debris in the conductive material. Further, if the residual debris is generated, the gate length and the gate width of the gate electrode are not within design values. Consequently, the device characteristics of the TFT may deviate from the determined design values.
However, the head of a conventional droplet discharge device can directly discharge droplets having a diameter smaller than the width of the gate electrode toward the electrode formation region. In this case, however, if accidental deflection occurs, there is a case where the droplet is adhered to portions other than the region where a gate electrode must be formed. Therefore, even in this case, the gate length and the gate width of the gate electrode that is finally obtained deviate from predetermined design values. Furthermore, if the size of the droplet becomes small, the volume of the droplet becomes small, and the number of droplets that are necessary to form the gate electrode increases accordingly. As a result, the time for forming the gate electrode increases.